Shoulder pain with arm muscle pain may be caused by overwork, shoulder disease, cervical spondylosis and other reasons. 1. Overexertion: Physiological transient pain caused by lactic acid accumulation due to excessive exercise and exertion of the upper limbs, shoulder pain together with arm muscle pain, which can be relieved after proper rest. 2. Shoulder diseases: Frozen shoulder, rotator cuff injury, fasciitis and other shoulder diseases lead to shoulder joint pain, and some of the pain will involve the upper arm, resulting in shoulder and arm muscle pain. 3. Cervical spondylosis: Neurogenic cervical spondylosis and other cervical spondylosis, resulting in the protruding intervertebral disc tissues compressing the innervating nerve roots of the upper limbs, causing shoulder pain. The pain radiates to the arm, fingers and other parts of the body, causing shoulder pain and muscle pain in the arm. There are many causes of this disease, if the pain can not be relieved after resting, you should go to the hospital in time to improve the relevant examination, clear diagnosis and then follow the doctor’s instructions for treatment.